const getUserChoice = (userInput) => {
  userInput = userInput.toLowerCase();
  if (userInput === 'rock' || userInput === 'paper' || userInput === 'scissors') {
    return userInput;
    } else {
      console.log('error');
    }
};

const getComputerChoice = () => {
 let randomNumber = Math.random();
  if (randomNumber < 0.33) {
    return 'rock';
  } else if (randomNumber > 0.34 && randomNumber < 0.66) {
    return 'paper';
  } else if (randomNumber > 0.67) {
    return 'scissors';
  }
};

const determineWinner = (userChoice, computerChoice) => {
  if (userChoice === computerChoice) {
    return 'tie';
  }
  if (userChoice === 'rock') {
    if (computerChoice === 'scissors') {
      return 'user won';
    } else {
      return 'computer won';
    }
  }
  if (userChoice === 'paper') {
    if (computerChoice === 'rock') {
      return 'user won';
    } else {
      return 'computer won';
    }
  }
  if (userChoice === 'scissors') {
    if (computerChoice === 'paper') {
      return 'user won';
    } else {
      return 'computer won';
    }
  }

};

const playGame = () => {
  const userChoice = getUserChoice('scissors');
  const computerChoice = getComputerChoice();
  console.log('user threw: ' + userChoice);
  console.log('computer threw: ' + computerChoice);
  console.log(determineWinner(userChoice, computerChoice));
};

playGame();